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Date: Fri, 29 May 2015 10:17:52 +0000
To: python-list@python.org
From: Kevin Peterson <qh.resu01@gmail.com>
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Subject: stdout of child process as an input of another thread in Python?
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Xref: csiph.com comp.lang.python:91443

Hi, 

I want to use the stdout of child process as an input of another thread, but some how I am not able to read the stdout.  Using Popen I have created a child process and stdout of it I have redirected to PIPE (because I don't want that to be printed on with my main process).  Now using this statement,"Line=Proc.stdout.readline()" I want to read stdout of child process and I have to do operation on that. but somehow i am not able to read from stdout of child process. 

Following is the code snapshot - 

    Proc = Popen(["python.exe","filename.py"],stdout=PIPE)
    
    while True:
                Line = Proc.stdout.readline()
                print Line

Here,
Filename.py(Child process) is continuously printing "Hello World!!" in place of reading stdout of child process. 



Thanks,
Kevin Peterson